1. Field of Invention
The present invention relates to a gate latch for a swingable gate.
2. Background
A gate latch is used for maintaining a swingable member in a closed condition. The swingable member may be a swinging door or gate that is hingedly attached to a relatively fixed member, such as a frame or post. Once latched, the swingable member remains in latched condition until it is manually released.
Automatic gate latches enable automatic latching of the gate latch into a catch member on the fixed post when the swingable member is pivoted about its hinges to a closed position. Such automatic gate latches typically include a latching bar fixed to the swingable member such that it projects beyond its non-hinged edge. The catch member, which is provided on the fixed member, has an outwardly divergent opening positioned to receive the latching bar within its opening, when the swingable member is moved towards the closing position. The latching bar is automatically guided to the latching slot of the catch member, where a latching dog, pivotally provided on the catch member, rotates out of the way, then automatically falls by gravity onto the latching bar, thereby engaging and retaining the latching bar in latched position.
The latching bar that is fixed on the swingable member may become misaligned with the divergent receiving portion of the catch member that is mounted on the fixed post of the gate, due to sagging of the swingable member. Due to such misalignment, latching may not take place as the swingable member approaches the closed position, thereby making the gate latch non-operational. Any attempt to forcibly align the latching bar with the divergent receiving portion of the catch member by physically lifting the gate by hinges, may stress the hinges as well as the latching bar. Further, in the event of such a misalignment, the latching bar may hit against the catch member during closing of the gate and may cause damage to it, particularly when the swingable member is slammed shut.
U.S. Pat. No. 3,266,831 discloses an automatic gate latch in which the latching bar is pivotally provided over a mounting bracket and extends through a slot in a flange provided on the edge of the mounting bracket. The latching bar is rotatable around a screw, which attaches the latching bar to the bracket at a pivot, by an angle from substantially horizontal to substantially above the horizontal. The pivotal arrangement may provide sufficient latitude for the latching bar to be positioned within the outwardly divergent opening of the catch member, even when there is misalignment between the latching bar and the catch member, due to sagging of the swingable member or the relatively fixed member. However, such an arrangement may put too much stress on the screw that holds the latching bar to the bracket, especially as the swinging member sags, or if too much force is exerted on the gate in the closed position. Failure of the screw causes the entire gate latch to fail.